Mobile phones are rapidly becoming essential tools for surfing the web, connecting with friends, and sharing and watching video online, and we're seeing these effects at YouTube. The YouTube mobile site is more popular than ever: site traffic grew by over 160% in 2009, and now millions of people all over the world are streaming tens of millions of videos every day on their mobile phones. The mobile space moves fast, so we've been working hard to roll out new features and functionality quickly, especially as more and more people adopt YouTube-capable phones.

The increased usage of high-end devices like the iPhone and Android is also making mobile advertising easier and more effective for advertisers. So today, we're launching ads on the home, search and browse pages of the American and Japanese YouTube mobile websites (m.youtube.com from your mobile browser). This is a great way for advertisers to reach YouTube viewers across multiple platforms. In fact, at launch YouTube will immediately provide one of the largest audiences for a mobile ad campaign anywhere on the mobile web. And because YouTube mobile attracts early adopters, the site can deliver to advertisers a coveted demographic of tech savvy trendsetters. We've already seen some early campaigns run on YouTube's mobile site by advertisers like Sony (for the DVD release of "District 9") and Kia, both of whom were able to easily reach their target audience, no matter where they were looking for video.

Our first tests of YouTube mobile ads — with brands ranging from L'Oreal to Land Rover — showed strong results related to click-throughs, user experience and brand awareness, and we've learned a lot in the months since then. As a result, ads on the YouTube mobile website will be banner ads sold on a full-day basis (like with the YouTube homepage on the web), making a mobile buy an easy and valuable addition to any YouTube campaign. For example, today Mazda is running a homepage ad on YouTube.com, and extended their campaign to run ads on our mobile site as well.

If you're interested in learning more, reach out to your YouTube or Google sales rep, or visit youtube.com/advertise.